Yesterday we looked at a mobile, maritime based wind turbine in Wind Hunter. Today, we’ll take a look at an airship based, floating turbine system from Magenn. In both cases, this is a practice of taking the turbine to richer wind resources than are available with traditional, fixed terrestrial systems.

Here’s the Magenn system in action:


Effectively, the system consists of a cylindrical helium airship where the cylinder rotates in the wind. The ends of the cylinder are coupled to generators. The entire system is tethered between 100 – 330m (300-1000 feet) above ground level to a winch system that can raise and lower the turbine to access the best wind resource or pull the turbine to earth during extreme weather. In addition to helium, the craft is also designed to make use of the magnus effect – spinning spheres create lift as is seen with golf and base balls.

In terms of efficiency, the traditional wind formula of (power = 0.5 x air density x swept area x velocity-cubed) is multiplied by 0.5 (50%) to get the efficiency of these turbines to account for the difference in swept area of a blade system vs. the cylinder. This reduced efficiency is offset by increased capacity factor due to better wind resource at higher altitudes. One other interesting aspect of these turbines is that they begin function with wind speeds of 2m/sec (4.5mph) and operate through speeds of 28m/sec (60+mph) which also increases the capacity factor of the device.

There is a 4kw system in existence and the company aims to release 10kw systems in 2008 at a target price range of $30,000 to $50,000 per unit. The 10kw system will also require around $3,500 in helium (not included) and will need to be properly permitted with local and federal aviation authorities. Lest one think this is not feasible, the US government has (and does) operate surveillance platforms consisting of tethered helim airships at heights over 5km (15,000 feet.)

Who knows, perhaps we’ll see these systems tethered and producing sometime in the near future.

This entry was posted on Thursday, May 31st, 2007 at 8:21 am and is filed under Wind.